Rock-drilling apparatus



Allril 1929- A. H. SKAER ET AL 1,708,975

' ROCK DRILLING APPARATUS Filed Dec. 18, 1925 2 Sheets-Sheet l Aprfl 16,1929.

A. H. SKAER ET AL Filed Dec. 18, 1925 2 Sheets-Sheet 2 Patented Apr. 161929.

.UN-ITED STATES PATENT OFFICE.

an'ruua H. sxann'ann Answer 11. KATTERJOHN, on DENVER, COLORADO,assrcnons,

BY ivinsnn assrenmnn'rs. r THE eannNEn-nnnvnn COMPANY, on QUINCY, ILLI-NOIS, A. CORPORATION OF DELATVARE.

ROCK-DRILLING APPARATUS.

Application filed December 18, 1925. SeriaLNo. 76,311.

The object of the present invention is to provide effective means of asimple character that willentirely exclude air from the bores of thesteel in rock drilling apparatus, while permitting the use of water, theeX- clusion'of air being under some conditions an absolutely essentialrequirement.

In the accompandng drawings': n

Figure 1 is a longitudinal sectional view through a drilling apparatus,showing the improved mechanism,

Figure 2 is a view partially in elevation and partially in section ofthe chuck-sleeve,

lligure 3 is a cross sectional view on the line of Figure 2,

Figure 1- is a view in elev tion of the PPQ l igure 5 is a sectionalView on the line 55 of Figure l. 1

In" the embodiment.disclosed a cylinder member is employed, including-abarrel 6,

having a piston chamber 7, in which reciprocates a hammer piston 8,having a hammer extension 9 onits front end. V

Ahousing 1(') is mounted on thefront end of the cylinder member, andlocated in i said housing, is a rotatable chuck sleeve 11.

This chuck sleeve, as shown particularly in Figure 2, has an enlargedrear head or flange 12, provided with rearwardly extending lugs 13 thatare interlocked with a sleeve let journaled on the front end of thebar-rel, and having a worm gear 15 mounted thereon.

The usual motor the casing of which is shown at 16, carried by thecylinder member, drives a worm '17 that is in mesh with the worm wheel.15, as a consequence of which, it will be evident that the motor 16 willeffeet the rotation of the chuck sleeve 11. The said chuck sleeve 11 hasin its front portion a set of splines 18.

Located within the chuck sleeve 11 is a tappet 19 that is provided onits rear portion with a series of splines 20 that .slidably interfit thesplines 18. The rear end 21 of this tappet is located in the path of theextension 9 of the piston hammer 8,. so that blows of impact areimparted to the tappet by direct contact between the extension 9 andsaid rear end 21. The tappet has an intermediate enlargement 22 and afront extension A retaining cap 24 surrounds the front extension 23 inadvance of the enlargement 22 and is held in place by bolts 25,preferably yieldingly held in their rearmost positions by springs 26mounted thereon. The tappet furthermore has a longitudinal socket 27opening through its front end, and havingthe walls of its rear portionthreaded, as shown at 28. The threads are preferably of relatively steeppitch, and are multiple-preferably triple. The drill steel, a portion ofwhich is shown at 29, has its rear end correspondinglythreaded, asillustrated at 30, so that it can be readily screwed into place. Thisdrill steel has the usual bore 31 therethrough. As clearly shown, thetappet 19 has a limited sliding movement in the chuck sleeve, but isrotate able therewith because of the iuterfitting splines. ltsrearwardmovement is determined by the abutment of the rear end 32 of theenlargement 22 against the front ends 33 of thesleeve splines 18 and bythe abutment of the rearends 34 of the tappet splines with an internalshoulder 36 formed in the chuck sleeve, abutting surfaces being thusprovided between the chuck sleeve and tappet. q a V r p Y Awater-conducting tube 37 extends axially through the hammer piston 9,through the rear eiul 21 of the tappet 19 andinto the drillsteel-receiving socket 27. A packing gland is formed in the tappetaround 8 this tube. To this end a plug, sleeve .or washer 38. is fittedinto. a socket 39 formed in rear of. thesteel-receiving socket 227, andis tightly compressed about the water tube 37. In advance of thispacking is located a washer or sleeve d0 of hard steel, and of greaterdiameter than the packing. This plug preferably projects into the rearend of the drill steel-receiving socket 27, so that the steel will abutagainst its front end, as shown in Figure 1, and said plug will thusconstitute means for transmitting the blows of impact to the drillsteel. For the purpose of allowing the escape of any motive fluid thatmay find its way past the extension 9 1 0 of the hammer piston 8, ports41 are formed through the chuck sleeve and open into the portion betweenthe front end of the hammer piston 8 9 and the rear end of the tappet,these ports communicating with an external groove 42, which in turn hasopen communication through one or more ports 43 with atmosphere.Preferably also vent channels 44 and 45 are formed in the exterior ofthe tappet so as to allow the air to escape from the open spaces withinthe chuck; I

\Vith this structure, it will be noted that the tappetis in the natureof a cap upon the rear end of the drill steel, and that the two aresecured together during the drilling operations. The tappet, however,can move freely, and thus deliver the necessary kinetic energy to thedrill steel. At the same time air cannot find a passage tot-he bore 31of the drill steel, because of the extended and large bearings around.

the tappet and the vent ports. Furthermore the} portion of the watertube extending a through the rear end of thetappet is effecshape,proportion'and minor details of construction may be'resorted to withoutdeparting from the spirit or sacrificing any of the advantages oftheinvention.

What'we claim, is:

1. In'rock drilling apparatus, the combination with a cylinder memberhaving an extension, of a hammer piston in the cylinder member', asleeve journaled on the extension, means engaged with the sleeve forrotating it, a housing in advance of the cylinder member, a chuck sleevejourn'aled in the housing and engaged with the sleeve on the extension,

, 2. In rock drilling apparatus, the combia tappet in the chuck sleeveto receive the piston hammer blows slidably interlocked therewith andhaving a steel-receiving socket in its front end.

nationwith a cylinder member, of a housing carried by the front endthereof, a retaining cap on the front end of the housing, a rotatablechuck sleeve in the housin and terminating at the cap, a tap )etslidably mounted in the chuck sleeve and projecting beyond the same andthrough the on p, said cap constituting means for retaining the tappetin the chucksleeve and said tappet having a steel-receiving socket inits front end, and

a hammer piston in the cylinder member that delivers blows against therear end of the tappet.

3. In rock drilling apparatus, the combination with a cylinder member,of a housing carried by the front end thereof, a retaining cap on thefront end of the housing, a rotatable chuck sleeve in the housing andterminating at the cap, a tappet slidably mounted in the chuck sleeveand projecting beyond the same and through the cap, said capconstituting means for retaining the tappet in the chuck sleeve and saidtappet having a steel-receiving socket in its front end, the walls ofthe rear portion of said socket having threads that terminate short ofthe front end of the socket, and a hammer piston in the cylinder memberthat delivers blows against the rear end of the tappet.

4. In rock drilling apparatus, the combination with a cylinder memberand a hammer piston therein, of a chuck at the front end of the cylindermember, a tappet slidably mounted in the chuck and receiving the blowsfrom the hammer piston, said tappet having a drill steel receivingsocket in its front end, a water tube extending through the hammerpiston and into the socket of the tappet, packing in the rear rtion ofthe tappet around the tube, an a blowtransmitting anvil block in thetappet in advance of the packing and abutting against the packing andagainst a portion of the tappet around the packing.

In testimony whereof, we aflix our signatures.

ARTHUR H. SKAER. AUGUST H. KATTERJOHN.

